Prenylated Flavonoids from Bark of Pithecellobium dulce

Prenylated flavonoids such as 3'prenyl-apigenin (1), 2-(4-hydroxy-3,5-bisisoprenyl)-8,8-dimethyl[2,3]pyrano) flavanone (2), 2(8'8'-dimethyl[2,3]pyrano-3,4-dehydro-cyclohexane)flavanone (3) and 2-(3'-isoprenyl)-4-oxocyclohexyl)- 4H-chromene-4,5,7(4aH,6H)-trione (4) were isolated from Pithecellobium dulce. Structures of isolated phytoconstituents were elucidated on the basis of spectroscopic analysis and physicochemical properties.